Tote boxes are general purpose containers, particularly for distribution of goods or their temporary storage. They are called upon to contain a wide variety of goods as they are shipped from a distribution point to a destination, for example, from a warehouse to retail outlets, from a manufacturer to a user, or within a manufacturing plant itself, for example.
The present invention relates to containers that may be nested within like containers so that their attached lids may shingle with the adjacent lids of the other containers, particularly for tote boxes and most particularly for tote boxes having two lids. The invention is particularly related to such boxes or containers that are molded, for example of a synthetic resin or plastic, so that the side and end walls are tapered towards the bottom to facilitate nesting of empty containers, wherein one or more lids are hinged respectively to the containers so that the lids may be swing generally 270.degree. from their closed position to a position wherein they shingle with respect to each other when the containers are nested, and which lids have reinforcing ribs and/or one or more flanges on each side to overlap the adjacent side wall in the closed position.
Shipping or storage boxes, are of course designated to be shipped full and are transported in fixed transport volume areas, such as the inside of a truck wherein only a fixed number of such full containers may be placed. It has been found desirable to return the empty containers in a nested condition wherein a larger number of such containers may be returned within the same fixed transport volume. Such advantages are fully discussed and recognized in U.S. Pat. No. 4,349,108, issued Sept. 14, 1982. However, such is a well known old problem and solution. A further discussion of such return trip nesting is to be found in the patent to Fleetwood U.S. Pat. No. 2,803,369, issued Aug. 20, 1957 and Best et al U.S. Pat. No. 2,112,451 issued Mar. 29, 1938. The latter patent employs attached lids and an elaborate hinge structure so that the lids may lay flat against the sides of the boxes or be shingled when a plurality of boxes are nested to address the problem of lid flare, so that a considerable number of receptacles may be compactly nested with relatively little addition to the transverse dimension of the box.
Lid flare is designated as the increase in horizontal dimension, on one side of the box, as measured perpendicular to the attached lid hinge axis, as caused by nesting of a plurality of such boxes and corresponding shingling of their attached lids.
Lid flare has been a well known problem in the art with many attempts made at reducing it.
A comparison of FIGS. 2 and 3 of the Weickart U.S. Pat. No. 3,383,009, issued May 14, 1968 clearly shows the advantages of reduced height in nesting containers for the return trip, and also clearly shows the problems of lid flare in increasing the horizontal dimension by nesting with shingled attached lids.
A particularly advantageous tote box was developed by the assignee of the present invention, and involved two attached lids, with ribbing for increasing the rigidity of the lids and lid sides having a side skirt flange, preferably together with an inboard flange forming channel-shaped portions, for overlying the corresponding sides of the box in the closed position; Bockenstette, U.S. Pat. No. 3,463,345, issued Aug. 26, 1969. In FIG. 8, the lid on the left hand side is accurately shown, schematically, in full lines for the open position. The dotted line representation of another lid shows its relative position, but if it were actually present, it would force the solid line lid to flare outwardly, because of interference between the reinforcing ribs and the skirt/flanges/side channel. For this particular type of tote box, the free edges of the lids interengage in the closed position as shown in FIG. 1, due to the presence of one or more teeth on each lid. The assignee later found that increasing the depth (measured vertically in the closed position) of the ribbing for the lids not only increased the strength of the lids, but greatly facilitated such interengaging when the lids were closed, because it is necessary to close the lids together and the Bockenstette box many times hung up and required additional manipulation, whereas the additional ribbing provided for easy closure. The ribbing also makes it more difficult for a thief to insert a hand through the interengaging portions of the lids, the lids are otherwise secured to the side walls in the closed position by a rivet, e.g.
Although the increased ribbing is considerably older than the patent to Frater, U.S. Pat. No. 4,161,261, issued July 17, 1979, such increased ribbing is clearly seen in the Frater patent for this type of box. Also, this patent discloses the conventional manner in which the lids are secured to the box side wall at the sides, as shown in FIGS. 5 and 6, which may be employed for the present invention. This box will nest with like boxes so that their lids shingle, as mentioned above.
The present invention is applicable to all of the above boxes and others wherein there is lid flare.